Computer Science 210:
Data Structures
Welcome to Data Structures!
• Data structures are fundamental building blocks of algorithms and programs
• Csci 210 is a study of data structures
• abstract data structures • design
• analysis
• implementation • use
• Prerequisites:
• csci 101 (at Bowdoin or in high-school) • In other words
• beginner knowledge of programming (in Java) • enjoy programming and problem solving
Logistics
• Instructor: Laura Toma
• office: Searles 219 • Office hours:
• T, Th 2-4pm
• quick questions any time I am in the office
• TA: Yuna Oh
• office hours: TBA
• Textbook:
• Lewis & Chase
• online: Sedgewick & Wayne, Programming in Java
• Website:
• http://www.bowdoin.edu/~ltoma/teaching/cs210/fall09/ • class not maintained on Blackboard
Course outline
• Week 1: Searching and sorting. • Week 2: Analysis of algorithms.
• Week 3: Object-oriented (OO) concepts. • Week 4: Stacks and queues.
• Week 5: Linked lists. • Week 6,7: Recursion. • --- Exam 1
• Week 8: Searching and backtracking. Breadth- and depth-first search. • Week 9: Trees and search trees.
• Week 10: Balanced binary search trees. • Week 11: Priority queues.
• Week 12: Maps and hash tables. • Week 13, 14: Networks. • --- Exam 2
Pong
Breakout
Sudoku
Boggle
Tetris
Terrains
...
Work and grading policy
• Class work:
• weekly homeworks and lab assignments (approx. 50%) • 2 exams (approx. 50%)
• readings, class participation, in-class assignments
• The class is programming-intensive
• Lab assignments are not meant to be finished during lab time. You have one week to
complete them.
• Handing in: hard copy + email
• on hard copy sign that you have followed class honor code
• Lab work: team of <= 2 people
• Late policy: 25% per day
• Why? it is absolutely essential that you do not fall behind • failure to turn in a lab ==> fail the class
Honor code
• Students are expected to follow the Bowdoin Computer Use Policy and the Academic Honor Code.
• You are encouraged to discuss ideas and techniques broadly with other class members, but not
specifics of assigned problems except as part of group projects.
• Discussions should be limited to questions that can be asked and answered without using any
written medium (e.g. pencil and paper or email).
• This means that at no time should a student read any code written by another student unless they
are part of the same group.
• Sharing of code or intermediate designs is expressly prohibited.
• The same rules apply once you have finished the course: sharing your code with other students will
be considered a violation of Bowdoin's honor code.
• Violation of this policy is grounds for me to initiate an action that would be filed with the Dean's office
and would come before the J Board.
• If you have any questions about this policy, PLEASE do not hesitate to contact me. This will be a
zero-tolerance policy.
• Don
ʼ
t leave lab for the last night!
More about the class
• The class is about designing, analyzing, implementing and using fundamental data
structures.
• 101
• you learnt how to use the basic constructs in Java. Put it differently, you learnt how to use a hammer and saw.
• focus was on learning the tools available when writing a program • syntax, conditionals, loops, arrays, etc
• 210
• Knowing how to use a hammer and saw does not mean you can build a house. In 210 youʼll learn how to build a house.
• youʼll learn more tools, and most importantly youʼll learn to put them together to create a large program • and...youʼll learn to LEARN
More about the class
• It is occasionally programming intensive
• However ... is NOT about programming
• but about programming methodology
• design + analysis + programming + debugging
• Programming language: Java. Why?
• makes graphics and web applications easy • available on all platforms
• new language, in fashion
• Most of the class will be independent of Java
• maybe next semester ...Python?
• Youʼll learn to distinguish between Java questions (check the Java doc pages to answer), and language-independent questions
• Java graphics NOT the core of the class
• Java graphics will be used to improve the interface of your programs • Usually the graphical part will be given, youʼll need to write the “core”
Labs
• Attendance is mandatory
• The labs are not meant to be finished during lab time
• Labs due one week after they are assigned; they are part of your homework
• Labs are not all equal
• in general, progressively harder
• at the beginning: lots of info guiding you towards the solution
• The labs are not always connected to the topic studied in class that week
• the focus is on solving a problem
• The labs are often harder than they look. Youʼll spend a lot of time understanding
what the task is. It is a good idea to read the lab beforehand, so that you can ask
many questions during lab time.
• Labs are challenging and fun. They are the most important learning tool
• you will learn in class
• you will REALLY learn while working out the labs
• times the process will seem painful, and occasionally you will find a lab unfair.
• TOGETHER
• During class time weʼll talk about data structures concepts, weʼll analyze various options and weʼll work out the implementation details for some of these options
• Often during class-time weʼll program together as a group • Occasionally thereʼll be in-class assignments and team work
• YOU
• youʼll learn to think like a computer scientist
• youʼll learn to find out what it takes to get a task accomplished • youʼll start your lab in a timely manner
• The bulk of your effort will be to get the lab assignments to work • You need to develop your code so that it can be debugged!!
• flowchart, develop incrementally, debug, test
Scenario
• You develop all classes at once. Nothing works! HELP!!!
• if code has too many errors, their combinations are infinite ==> impossible to debug
• Moral: structure your code so that you implement one feature at a time, you debug it and test it, and then move on.
• You get stuck in Java graphics (GUI) before solving the actual problem.
• Why donʼt the buttons show?
• Moral: Solve the core of the problem first, with a simple interface. If you have time at the end you can make your GUI more fancy.
More Expectations
• Problem: various backgrounds
• 101 A vs. 101B • 101 vs. highschool
• highschool 1 vs. highschool 2
• Willingness to work in a group environment
• Patience with material that is not new and when class is slow
• participate
• share with others
• Ask plenty of questions when something is unclear
• Goal: we want to work as a class
Class Outcomes
• You will learn the fundamental data structures:
• lists, vectors stacks, queues, priority queues, trees, hash tables and maps
• Design: you will learn to model and come up with a solution to a problem
• modularity, data abstraction, building blocks
• Analysis: you will learn to analyze the efficiency of your solution
• you will learn to use efficiency considerations to decide the choice of data structures
• Program development: you will learn the importance of each step in getting a
program to work: design, debug, test
• Practice of programming: • Simplicity
• clarity • generality
This being said...
• Yes, 210 will be challenging
• But, most of the people who take 210
• like it
• say it is one of the most fun classes they took • continue with Computer Science
• 210 is the pre-requisite for all other classes
• If you like 210, you should think about majoring or minoring in computer science
